Long noncoding RNA WT1-AS has been demonstrated as a potential tumor suppressor in gastric cancer. However, the functions of WT1-AS in other types of cancer remain unclear. Our study was therefore performed to explore the role of WT1-AS in triple-negative breast cancer (TNBC). Tissue specimens were obtained from 62 TNBC patients included in this study. A TNBC cell line BT-549 was used as the cell model of TNBC. Gene expression was detected by qPCR and Western blot. Overexpression experiments were used to analyze gene interactions. Transwell assays were used to explore the effects of transfections on cell invasion and migration. We found that WT1-AS was downregulated in TNBC tissues than in nontumor tissues and decreased with increase in clinical stages. Transforming growth factor β1 (TGF-β1) was upregulated in TNBC tissues and inversely correlated with WT1-AS. TGF-β1 overexpression did not significantly affect WT1-AS in BT-549 cells, but WT1-AS negatively regulated the expression of TGF-β1. WT1-AS overexpression caused inhibited migration and invasion of TNBC cells. TGF-β1 overexpression showed opposite functions and reduced the effects of WT1-AS overexpression. WT1-AS may downregulate TGF-β to inhibit the migration and invasion of TNBC cells.